Tottenham Hotspur have confirmed the signing of the Mexican playmaker Giovani Dos Santos from Barcelona.

Both clubs had announced the move last week, for a fee of £4.7m rising to a potential £8.6m depending on appearances, subject to the player passing a medical and agreeing personal terms.

In a statement on the club's website, Tottenham confirmed that these formalities had now been concluded: "The 19-year-old Mexican international this week passed a medical and agreed terms to complete his move from Barcelona."

Dos Santos, who can play up front or on either wing, and joins the Croatian Luka Modric in a potentially mouthwatering attack for next season, spoke of his delight at the move.

"It is a dream for me to come to a big club like Spurs. I've come here to further explore my qualities and give my all for my new team. As a young player I have come to a club where I feel there are many opportunities for me."

Coach Juande Ramos also expressed his delight at securing the signature of Dos Santos, who had interested Chelsea and Manchester City. "For us it is an exciting signing because he has excellent quality, he operates well in different positions and, above all, is technically excellent," he said.

Spurs' director of football Damien Comolli has been criticised by fans after some less than successful signings last summer, but is confident that Dos Santos can make an impact in England: "Giovani possesses a great combination of physical power and explosivity, along with fine technical skills. He is someone who can create and score goals.

"He is young but not without experience and will be a great asset for the Club. The fact we have a Spanish speaking coaching staff, as well as Gilberto, will help him adapt, settle quickly and I believe he has the skills to be successful in England."

Elsewhere, Lazio have completed the signing of Czech Republic defender David Rozehnal from Newcastle. The 27-year-old, who joined the Magpies in a £2.9m deal from Paris St Germain last summer, had been on loan at the Italian club since January. Lazio have now exercised their option to sign the player permanently in a move Newcastle say will enable them to recover the fee they paid PSG.

Plymouth teenager Aaron Spear is in talks with two Premier League clubs over a move to the top flight. The 15-year-old striker has recently attracted interest from Newcastle as well as another unnamed top tier club and has now opened talks over a possible move.

Plymouth's chief executive Michael Dunford told the club's website: "We don't want Aaron to leave us but he is determined to speak to these Premiership teams. We have reluctantly therefore given him permission to talk to them."

Spear is currently on schoolboy terms with Argyle and the club would be entitled to receive a fee if he decided to move on.